Mercury in the marine boundary layer and seawater of the South China Sea: Concentrations, sea/air flux, and implication for land outflow

作者：Xuewu Fu, Xinbin Feng, Gan Zhang, Weihai Xu, Xiangdong D. Li, Hen Yao, Peng Liang, Jun Li, Jonas Olof Sommar, Runsheng Yin, Na Liu · 发表于：Journal of Geophysical Research Atmospheres · 年份：2010 · DOI：10.1029/2009jd012958 · 被引用次数：329 · 研究领域：Mercury impact and mitigation studies、Marine animal studies overview、Toxic Organic Pollutants Impact

Using R/V Shiyan 3 as a sampling platform, measurements of gaseous elemental mercury (GEM), surface seawater total mercury (THg), methyl mercury (MeHg), and dissolved gaseous mercury (DGM) were carried out above and in the South China Sea (SCS). Measurements were collected for 2 weeks (10 to 28 August 2007) during an oceanographic expedition, which circumnavigated the northern SCS from Guangzhou (Canton), Hainan Inland, the Philippines, and back to Guangzhou. GEM concentrations over the northern SCS ranged from 1.04 to 6.75 ng m−3 (mean: 2.62 ng m−3, median: 2.24 ng m−3). The spatial distribution of GEM was characterized by elevated concentrations near the coastal sites adjacent to mainland China and lower concentrations at stations in the open sea. Trajectory analysis revealed that high concentrations of GEM were generally related to air masses from south China and the Indochina peninsula, while lower concentrations of GEM were related to air masses from the open sea area, reflecting great Hg emissions from south China and Indochina peninsula. The mean concentrations of THg, MeHg, and DGM in surface seawater were 1.2 ± 0.3 ng L−1, 0.12 ± 0.05 ng L−1, and 36.5 ± 14.9 pg L−1, respectively. In general, THg and MeHg levels in the northern SCS were higher compared to results reported from most other oceans/seas. Elevated THg levels in the study area were likely attributed to significant Hg delivery from surrounding areas of the SCS primarily via atmospheric deposition and riverin...